df <- data.frame(A = 1:10, B = 1:10, type = rep(letters[1:5], each = 2)); df
## A B type
## 1 1 1 a
## 2 2 2 a
## 3 3 3 b
## 4 4 4 b
## 5 5 5 c
## 6 6 6 c
## 7 7 7 d
## 8 8 8 d
## 9 9 9 e
## 10 10 10 e
result <- data.frame(A = c(3, 7, 11, 15, 19), B = c(3, 7, 11, 15, 19), type = letters[1:5]); result
## A B type
## 1 3 3 a
## 2 7 7 b
## 3 11 11 c
## 4 15 15 d
## 5 19 19 e
library(tidyverse)
df %>%
group_by(type) %>%
summarise_all(funs(sum)) %>%
select(A,B,type)
## # A tibble: 5 x 3
## A B type
## <int> <int> <fct>
## 1 3 3 a
## 2 7 7 b
## 3 11 11 c
## 4 15 15 d
## 5 19 19 e
# 排序